Module No. 5553 Adjusting the Current Time Setting Use the procedures below to adjust the current date and time settings, and to select a Home City. Setting a Home City Setting the Time/Date Switching between 12-hour and 24-hour Timekeeping Time Adjustment Adjusting the Current Time Setting Back Next Home CASIO official home page. How To Change Time On A Casio G-Shock Watch? - YouTube. This is how to set the time on your Casio g-shock watch easily.If you have any other questions, leave a comment below and I will guide you Current models of G-shock change the time zone automatically, so the first thing you are prompted to do is choose a city code for where you live or at least for a city in the same time zone. Specifying a World Time City with CASIO WATCHES causes the watch's World Time City to change accordingly. The standard time/summer time setting of the World Time will be adjusted automatically without any watch operation required by you. Note CASIO WATCHES World Time lets you select from among approximately 300 cities as the World Time City. F1wG4We.